HARS2 and Perrault syndrome: In this study, we established a hair cell specific knockout mouse model for the mitochondrial histidyl-tRNA synthetase encoding gene Hars2, whose recessive mutations lead to decreased levels of aminoacylated tRNAHis and sensorineural hearing loss with female ovarian dysgenesis (Perrault syndrome 2) in humans (Pierce et al., 2011), and whose overexpression restores mitochondrial dysfunction caused by a deafness-associated m.12201T > C mutation in tRNAHis (Gong et al., 2020).